Threat Description



Category: Malware
Type: TrojanVirus
Platform: W97M
Date Discovered: June 27, 2006
Aliases: Kukudro.A, W97M/Kukudro.A, Trojan-Dropper.MSWord.Lafool.i


Kukudro is an MS Word macro trojan dropper written in Visual Basic for Applications (VBA). The dropper has been spammed in various e-mails as my_Notebook.doc inside a zip archive. Once a user opens the document, it drops and runs a binary executable.


Automatic action

Once detected, the F-Secure security product will automatically disinfect the suspect file by either deleting it or renaming it.

More scanning & removal options

More information on scanning or removal options is available in the documentation for your F-Secure security product on the Downloads section of our Home - Global site.

You may also refer to the Knowledge Base on the F-Secure Community site for more information.

Contact Support

For further assistance, F-Secure customers can request support online via the Request support or the Chat forms on our Home - Global site.

Technical Details

When the infected Word document is opened, the macro code inside of it will be executed. It will decode a binary file from its code and drop it as 666inse_1.exe to the root of the C: drive. Then the macro will execute the dropped 666inse_1.exe file and end. The binary executable is a trojan downloader called Small.dcu.

Please note that you are using Office 2003 or later the macro will be executed only if macros have been enabled from Word's security settings. Otherwise, the trojan uses a vulnerability in MS Word 97, 2000 and XP and will run although macros are disabled. You can find more about this vulnerability here:


Suspect a file or URL was wrongly detected? Submit a sample to our Labs for analysis

Submit Now

Give And Get Advice

Give advice. Get advice. Share the knowledge on our free discussion forum.

Learn More